( function () {
class GLTFLoader extends THREE.Loader {
  constructor(manager) {
    super(manager);
    this.dracoLoader = null;
    this.ktx2Loader = null;
    this.meshoptDecoder = null;
    this.pluginCallbacks = [];
    this.register(function (parser) {
      return new GLTFMaterialsClearcoatExtension(parser);
    });
    this.register(function (parser) {
      return new GLTFTextureBasisUExtension(parser);
    });
    this.register(function (parser) {
      return new GLTFTextureWebPExtension(parser);
    });
    this.register(function (parser) {
      return new GLTFMaterialsTransmissionExtension(parser);
    });
    this.register(function (parser) {
      return new GLTFLightsExtension(parser);
    });
    this.register(function (parser) {
      return new GLTFMeshoptCompression(parser);
    });
  }

  load(url, onLoad, onProgress, onError) {
    const scope = this;
    let resourcePath;

    if (this.resourcePath !== '') {
      resourcePath = this.resourcePath;
    } else if (this.path !== '') {
      resourcePath = this.path;
    } else {
      resourcePath = THREE.LoaderUtils.extractUrlBase(url);
    } // Tells the LoadingManager to track an extra item, which resolves after
    // the model is fully loaded. This means the count of items loaded will
    // be incorrect, but ensures manager.onLoad() does not fire early.


    this.manager.itemStart(url);

    const _onError = function (e) {
      if (onError) {
        onError(e);
      } else {
        console.error(e);
      }

      scope.manager.itemError(url);
      scope.manager.itemEnd(url);
    };

    const loader = new THREE.FileLoader(this.manager);
    loader.setPath(this.path);
    loader.setResponseType('arraybuffer');
    loader.setRequestHeader(this.requestHeader);
    loader.setWithCredentials(this.withCredentials);
    loader.load(url, function (data) {
      try {
        scope.parse(data, resourcePath, function (gltf) {
          onLoad(gltf);
          scope.manager.itemEnd(url);
        }, _onError);
      } catch (e) {
        _onError(e);
      }
    }, onProgress, _onError);
  }

  setDRACOLoader(dracoLoader) {
    this.dracoLoader = dracoLoader;
    return this;
  }

  setDDSLoader() {
    throw new Error('THREE.GLTFLoader: "MSFT_texture_dds" no longer supported. Please update to "KHR_texture_basisu".');
  }

  setKTX2Loader(ktx2Loader) {
    this.ktx2Loader = ktx2Loader;
    return this;
  }

  setMeshoptDecoder(meshoptDecoder) {
    this.meshoptDecoder = meshoptDecoder;
    return this;
  }

  register(callback) {
    if (this.pluginCallbacks.indexOf(callback) === -1) {
      this.pluginCallbacks.push(callback);
    }

    return this;
  }

  unregister(callback) {
    if (this.pluginCallbacks.indexOf(callback) !== -1) {
      this.pluginCallbacks.splice(this.pluginCallbacks.indexOf(callback), 1);
    }

    return this;
  }

  parse(data, path, onLoad, onError) {
    let content;
    const extensions = {};
    const plugins = {};

    if (typeof data === 'string') {
      content = data;
    } else {
      const magic = THREE.LoaderUtils.decodeText(new Uint8Array(data, 0, 4));

      if (magic === BINARY_EXTENSION_HEADER_MAGIC) {
        try {
          extensions[EXTENSIONS.KHR_BINARY_GLTF] = new GLTFBinaryExtension(data);
        } catch (error) {
          if (onError) onError(error);
          return;
        }

        content = extensions[EXTENSIONS.KHR_BINARY_GLTF].content;
      } else {
        content = THREE.LoaderUtils.decodeText(new Uint8Array(data));
      }
    }

    const json = JSON.parse(content);

    if (json.asset === undefined || json.asset.version[0] < 2) {
      if (onError) onError(new Error('THREE.GLTFLoader: Unsupported asset. glTF versions >=2.0 are supported.'));
      return;
    }

    const parser = new GLTFParser(json, {
      path: path || this.resourcePath || '',
      crossOrigin: this.crossOrigin,
      requestHeader: this.requestHeader,
      manager: this.manager,
      ktx2Loader: this.ktx2Loader,
      meshoptDecoder: this.meshoptDecoder
    });
    parser.fileLoader.setRequestHeader(this.requestHeader);

    for (let i = 0; i < this.pluginCallbacks.length; i++) {
      const plugin = this.pluginCallbacks[i](parser);
      plugins[plugin.name] = plugin; // Workaround to avoid determining as unknown extension
      // in addUnknownExtensionsToUserData().
      // Remove this workaround if we move all the existing
      // extension handlers to plugin system

      extensions[plugin.name] = true;
    }

    if (json.extensionsUsed) {
      for (let i = 0; i < json.extensionsUsed.length; ++i) {
        const extensionName = json.extensionsUsed[i];
        const extensionsRequired = json.extensionsRequired || [];

        switch (extensionName) {
          case EXTENSIONS.KHR_MATERIALS_UNLIT:
            extensions[extensionName] = new GLTFMaterialsUnlitExtension();
            break;

          case EXTENSIONS.KHR_MATERIALS_PBR_SPECULAR_GLOSSINESS:
            extensions[extensionName] = new GLTFMaterialsPbrSpecularGlossinessExtension();
            break;

          case EXTENSIONS.KHR_DRACO_MESH_COMPRESSION:
            extensions[extensionName] = new GLTFDracoMeshCompressionExtension(json, this.dracoLoader);
            break;

          case EXTENSIONS.KHR_TEXTURE_TRANSFORM:
            extensions[extensionName] = new GLTFTextureTransformExtension();
            break;

          case EXTENSIONS.KHR_MESH_QUANTIZATION:
            extensions[extensionName] = new GLTFMeshQuantizationExtension();
            break;

          default:
            if (extensionsRequired.indexOf(extensionName) >= 0 && plugins[extensionName] === undefined) {
              console.warn('THREE.GLTFLoader: Unknown extension "' + extensionName + '".');
            }

        }
      }
    }

    parser.setExtensions(extensions);
    parser.setPlugins(plugins);
    parser.parse(onLoad, onError);
  }

}
/* GLTFREGISTRY */


function GLTFRegistry() {
  let objects = {};
  return {
    get: function (key) {
      return objects[key];
    },
    add: function (key, object) {
      objects[key] = object;
    },
    remove: function (key) {
      delete objects[key];
    },
    removeAll: function () {
      objects = {};
    }
  };
}
/*********************************/

/********** EXTENSIONS ***********/

/*********************************/


const EXTENSIONS = {
  KHR_BINARY_GLTF: 'KHR_binary_glTF',
  KHR_DRACO_MESH_COMPRESSION: 'KHR_draco_mesh_compression',
  KHR_LIGHTS_PUNCTUAL: 'KHR_lights_punctual',
  KHR_MATERIALS_CLEARCOAT: 'KHR_materials_clearcoat',
  KHR_MATERIALS_PBR_SPECULAR_GLOSSINESS: 'KHR_materials_pbrSpecularGlossiness',
  KHR_MATERIALS_TRANSMISSION: 'KHR_materials_transmission',
  KHR_MATERIALS_UNLIT: 'KHR_materials_unlit',
  KHR_TEXTURE_BASISU: 'KHR_texture_basisu',
  KHR_TEXTURE_TRANSFORM: 'KHR_texture_transform',
  KHR_MESH_QUANTIZATION: 'KHR_mesh_quantization',
  EXT_TEXTURE_WEBP: 'EXT_texture_webp',
  EXT_MESHOPT_COMPRESSION: 'EXT_meshopt_compression'
};
/**
 * Punctual Lights Extension
 *
 * Specification: https://github.com/KhronosGroup/glTF/tree/master/extensions/2.0/Khronos/KHR_lights_punctual
 */

class GLTFLightsExtension {
  constructor(parser) {
    this.parser = parser;
    this.name = EXTENSIONS.KHR_LIGHTS_PUNCTUAL; // THREE.Object3D instance caches

    this.cache = {
      refs: {},
      uses: {}
    };
  }

  _markDefs() {
    const parser = this.parser;
    const nodeDefs = this.parser.json.nodes || [];

    for (let nodeIndex = 0, nodeLength = nodeDefs.length; nodeIndex < nodeLength; nodeIndex++) {
      const nodeDef = nodeDefs[nodeIndex];

      if (nodeDef.extensions && nodeDef.extensions[this.name] && nodeDef.extensions[this.name].light !== undefined) {
        parser._addNodeRef(this.cache, nodeDef.extensions[this.name].light);
      }
    }
  }

  _loadLight(lightIndex) {
    const parser = this.parser;
    const cacheKey = 'light:' + lightIndex;
    let dependency = parser.cache.get(cacheKey);
    if (dependency) return dependency;
    const json = parser.json;
    const extensions = json.extensions && json.extensions[this.name] || {};
    const lightDefs = extensions.lights || [];
    const lightDef = lightDefs[lightIndex];
    let lightNode;
    const color = new THREE.Color(0xffffff);
    if (lightDef.color !== undefined) color.fromArray(lightDef.color);
    const range = lightDef.range !== undefined ? lightDef.range : 0;

    switch (lightDef.type) {
      case 'directional':
        lightNode = new THREE.DirectionalLight(color);
        lightNode.target.position.set(0, 0, -1);
        lightNode.add(lightNode.target);
        break;

      case 'point':
        lightNode = new THREE.PointLight(color);
        lightNode.distance = range;
        break;

      case 'spot':
        lightNode = new THREE.SpotLight(color);
        lightNode.distance = range; // Handle spotlight properties.

        lightDef.spot = lightDef.spot || {};
        lightDef.spot.innerConeAngle = lightDef.spot.innerConeAngle !== undefined ? lightDef.spot.innerConeAngle : 0;
        lightDef.spot.outerConeAngle = lightDef.spot.outerConeAngle !== undefined ? lightDef.spot.outerConeAngle : Math.PI / 4.0;
        lightNode.angle = lightDef.spot.outerConeAngle;
        lightNode.penumbra = 1.0 - lightDef.spot.innerConeAngle / lightDef.spot.outerConeAngle;
        lightNode.target.position.set(0, 0, -1);
        lightNode.add(lightNode.target);
        break;

      default:
        throw new Error('THREE.GLTFLoader: Unexpected light type: ' + lightDef.type);
    } // Some lights (e.g. spot) default to a position other than the origin. Reset the position
    // here, because node-level parsing will only override position if explicitly specified.


    lightNode.position.set(0, 0, 0);
    lightNode.decay = 2;
    if (lightDef.intensity !== undefined) lightNode.intensity = lightDef.intensity;
    lightNode.name = parser.createUniqueName(lightDef.name || 'light_' + lightIndex);
    dependency = Promise.resolve(lightNode);
    parser.cache.add(cacheKey, dependency);
    return dependency;
  }

  createNodeAttachment(nodeIndex) {
    const self = this;
    const parser = this.parser;
    const json = parser.json;
    const nodeDef = json.nodes[nodeIndex];
    const lightDef = nodeDef.extensions && nodeDef.extensions[this.name] || {};
    const lightIndex = lightDef.light;
    if (lightIndex === undefined) return null;
    return this._loadLight(lightIndex).then(function (light) {
      return parser._getNodeRef(self.cache, lightIndex, light);
    });
  }

}
/**
 * Unlit Materials Extension
 *
 * Specification: https://github.com/KhronosGroup/glTF/tree/master/extensions/2.0/Khronos/KHR_materials_unlit
 */


class GLTFMaterialsUnlitExtension {
  constructor() {
    this.name = EXTENSIONS.KHR_MATERIALS_UNLIT;
  }

  getMaterialType() {
    return THREE.MeshBasicMaterial;
  }

  extendParams(materialParams, materialDef, parser) {
    const pending = [];
    materialParams.color = new THREE.Color(1.0, 1.0, 1.0);
    materialParams.opacity = 1.0;
    const metallicRoughness = materialDef.pbrMetallicRoughness;

    if (metallicRoughness) {
      if (Array.isArray(metallicRoughness.baseColorFactor)) {
        const array = metallicRoughness.baseColorFactor;
        materialParams.color.fromArray(array);
        materialParams.opacity = array[3];
      }

      if (metallicRoughness.baseColorTexture !== undefined) {
        pending.push(parser.assignTexture(materialParams, 'map', metallicRoughness.baseColorTexture));
      }
    }

    return Promise.all(pending);
  }

}
/**
 * Clearcoat Materials Extension
 *
 * Specification: https://github.com/KhronosGroup/glTF/tree/master/extensions/2.0/Khronos/KHR_materials_clearcoat
 */


class GLTFMaterialsClearcoatExtension {
  constructor(parser) {
    this.parser = parser;
    this.name = EXTENSIONS.KHR_MATERIALS_CLEARCOAT;
  }

  getMaterialType(materialIndex) {
    const parser = this.parser;
    const materialDef = parser.json.materials[materialIndex];
    if (!materialDef.extensions || !materialDef.extensions[this.name]) return null;
    return THREE.MeshPhysicalMaterial;
  }

  extendMaterialParams(materialIndex, materialParams) {
    const parser = this.parser;
    const materialDef = parser.json.materials[materialIndex];

    if (!materialDef.extensions || !materialDef.extensions[this.name]) {
      return Promise.resolve();
    }

    const pending = [];
    const extension = materialDef.extensions[this.name];

    if (extension.clearcoatFactor !== undefined) {
      materialParams.clearcoat = extension.clearcoatFactor;
    }

    if (extension.clearcoatTexture !== undefined) {
      pending.push(parser.assignTexture(materialParams, 'clearcoatMap', extension.clearcoatTexture));
    }

    if (extension.clearcoatRoughnessFactor !== undefined) {
      materialParams.clearcoatRoughness = extension.clearcoatRoughnessFactor;
    }

    if (extension.clearcoatRoughnessTexture !== undefined) {
      pending.push(parser.assignTexture(materialParams, 'clearcoatRoughnessMap', extension.clearcoatRoughnessTexture));
    }

    if (extension.clearcoatNormalTexture !== undefined) {
      pending.push(parser.assignTexture(materialParams, 'clearcoatNormalMap', extension.clearcoatNormalTexture));

      if (extension.clearcoatNormalTexture.scale !== undefined) {
        const scale = extension.clearcoatNormalTexture.scale; // https://github.com/mrdoob/three.js/issues/11438#issuecomment-507003995

        materialParams.clearcoatNormalScale = new THREE.Vector2(scale, -scale);
      }
    }

    return Promise.all(pending);
  }

}
/**
 * Transmission Materials Extension
 *
 * Specification: https://github.com/KhronosGroup/glTF/tree/master/extensions/2.0/Khronos/KHR_materials_transmission
 * Draft: https://github.com/KhronosGroup/glTF/pull/1698
 */


class GLTFMaterialsTransmissionExtension {
  constructor(parser) {
    this.parser = parser;
    this.name = EXTENSIONS.KHR_MATERIALS_TRANSMISSION;
  }

  getMaterialType(materialIndex) {
    const parser = this.parser;
    const materialDef = parser.json.materials[materialIndex];
    if (!materialDef.extensions || !materialDef.extensions[this.name]) return null;
    return THREE.MeshPhysicalMaterial;
  }

  extendMaterialParams(materialIndex, materialParams) {
    const parser = this.parser;
    const materialDef = parser.json.materials[materialIndex];

    if (!materialDef.extensions || !materialDef.extensions[this.name]) {
      return Promise.resolve();
    }

    const pending = [];
    const extension = materialDef.extensions[this.name];

    if (extension.transmissionFactor !== undefined) {
      materialParams.transmission = extension.transmissionFactor;
    }

    if (extension.transmissionTexture !== undefined) {
      pending.push(parser.assignTexture(materialParams, 'transmissionMap', extension.transmissionTexture));
    }

    return Promise.all(pending);
  }

}
/**
 * BasisU THREE.Texture Extension
 *
 * Specification: https://github.com/KhronosGroup/glTF/tree/master/extensions/2.0/Khronos/KHR_texture_basisu
 */


class GLTFTextureBasisUExtension {
  constructor(parser) {
    this.parser = parser;
    this.name = EXTENSIONS.KHR_TEXTURE_BASISU;
  }

  loadTexture(textureIndex) {
    const parser = this.parser;
    const json = parser.json;
    const textureDef = json.textures[textureIndex];

    if (!textureDef.extensions || !textureDef.extensions[this.name]) {
      return null;
    }

    const extension = textureDef.extensions[this.name];
    const source = json.images[extension.source];
    const loader = parser.options.ktx2Loader;

    if (!loader) {
      if (json.extensionsRequired && json.extensionsRequired.indexOf(this.name) >= 0) {
        throw new Error('THREE.GLTFLoader: setKTX2Loader must be called before loading KTX2 textures');
      } else {
        // Assumes that the extension is optional and that a fallback texture is present
        return null;
      }
    }

    return parser.loadTextureImage(textureIndex, source, loader);
  }

}
/**
 * WebP THREE.Texture Extension
 *
 * Specification: https://github.com/KhronosGroup/glTF/tree/master/extensions/2.0/Vendor/EXT_texture_webp
 */


class GLTFTextureWebPExtension {
  constructor(parser) {
    this.parser = parser;
    this.name = EXTENSIONS.EXT_TEXTURE_WEBP;
    this.isSupported = null;
  }

  loadTexture(textureIndex) {
    const name = this.name;
    const parser = this.parser;
    const json = parser.json;
    const textureDef = json.textures[textureIndex];

    if (!textureDef.extensions || !textureDef.extensions[name]) {
      return null;
    }

    const extension = textureDef.extensions[name];
    const source = json.images[extension.source];
    let loader = parser.textureLoader;

    if (source.uri) {
      const handler = parser.options.manager.getHandler(source.uri);
      if (handler !== null) loader = handler;
    }

    return this.detectSupport().then(function (isSupported) {
      if (isSupported) return parser.loadTextureImage(textureIndex, source, loader);

      if (json.extensionsRequired && json.extensionsRequired.indexOf(name) >= 0) {
        throw new Error('THREE.GLTFLoader: WebP required by asset but unsupported.');
      } // Fall back to PNG or JPEG.


      return parser.loadTexture(textureIndex);
    });
  }

  detectSupport() {
    if (!this.isSupported) {
      this.isSupported = new Promise(function (resolve) {
        const image = new Image(); // Lossy test image. Support for lossy images doesn't guarantee support for all
        // WebP images, unfortunately.

        image.src = '';

        image.onload = image.onerror = function () {
          resolve(image.height === 1);
        };
      });
    }

    return this.isSupported;
  }

}
/**
 * meshopt BufferView Compression Extension
 *
 * Specification: https://github.com/KhronosGroup/glTF/tree/master/extensions/2.0/Vendor/EXT_meshopt_compression
 */


class GLTFMeshoptCompression {
  constructor(parser) {
    this.name = EXTENSIONS.EXT_MESHOPT_COMPRESSION;
    this.parser = parser;
  }

  loadBufferView(index) {
    const json = this.parser.json;
    const bufferView = json.bufferViews[index];

    if (bufferView.extensions && bufferView.extensions[this.name]) {
      const extensionDef = bufferView.extensions[this.name];
      const buffer = this.parser.getDependency('buffer', extensionDef.buffer);
      const decoder = this.parser.options.meshoptDecoder;

      if (!decoder || !decoder.supported) {
        if (json.extensionsRequired && json.extensionsRequired.indexOf(this.name) >= 0) {
          throw new Error('THREE.GLTFLoader: setMeshoptDecoder must be called before loading compressed files');
        } else {
          // Assumes that the extension is optional and that fallback buffer data is present
          return null;
        }
      }

      return Promise.all([buffer, decoder.ready]).then(function (res) {
        const byteOffset = extensionDef.byteOffset || 0;
        const byteLength = extensionDef.byteLength || 0;
        const count = extensionDef.count;
        const stride = extensionDef.byteStride;
        const result = new ArrayBuffer(count * stride);
        const source = new Uint8Array(res[0], byteOffset, byteLength);
        decoder.decodeGltfBuffer(new Uint8Array(result), count, stride, source, extensionDef.mode, extensionDef.filter);
        return result;
      });
    } else {
      return null;
    }
  }

}
/* BINARY EXTENSION */


const BINARY_EXTENSION_HEADER_MAGIC = 'glTF';
const BINARY_EXTENSION_HEADER_LENGTH = 12;
const BINARY_EXTENSION_CHUNK_TYPES = {
  JSON: 0x4E4F534A,
  BIN: 0x004E4942
};

class GLTFBinaryExtension {
  constructor(data) {
    this.name = EXTENSIONS.KHR_BINARY_GLTF;
    this.content = null;
    this.body = null;
    const headerView = new DataView(data, 0, BINARY_EXTENSION_HEADER_LENGTH);
    this.header = {
      magic: THREE.LoaderUtils.decodeText(new Uint8Array(data.slice(0, 4))),
      version: headerView.getUint32(4, true),
      length: headerView.getUint32(8, true)
    };

    if (this.header.magic !== BINARY_EXTENSION_HEADER_MAGIC) {
      throw new Error('THREE.GLTFLoader: Unsupported glTF-Binary header.');
    } else if (this.header.version < 2.0) {
      throw new Error('THREE.GLTFLoader: Legacy binary file detected.');
    }

    const chunkContentsLength = this.header.length - BINARY_EXTENSION_HEADER_LENGTH;
    const chunkView = new DataView(data, BINARY_EXTENSION_HEADER_LENGTH);
    let chunkIndex = 0;

    while (chunkIndex < chunkContentsLength) {
      const chunkLength = chunkView.getUint32(chunkIndex, true);
      chunkIndex += 4;
      const chunkType = chunkView.getUint32(chunkIndex, true);
      chunkIndex += 4;

      if (chunkType === BINARY_EXTENSION_CHUNK_TYPES.JSON) {
        const contentArray = new Uint8Array(data, BINARY_EXTENSION_HEADER_LENGTH + chunkIndex, chunkLength);
        this.content = THREE.LoaderUtils.decodeText(contentArray);
      } else if (chunkType === BINARY_EXTENSION_CHUNK_TYPES.BIN) {
        const byteOffset = BINARY_EXTENSION_HEADER_LENGTH + chunkIndex;
        this.body = data.slice(byteOffset, byteOffset + chunkLength);
      } // Clients must ignore chunks with unknown types.


      chunkIndex += chunkLength;
    }

    if (this.content === null) {
      throw new Error('THREE.GLTFLoader: JSON content not found.');
    }
  }

}
/**
 * DRACO THREE.Mesh Compression Extension
 *
 * Specification: https://github.com/KhronosGroup/glTF/tree/master/extensions/2.0/Khronos/KHR_draco_mesh_compression
 */


class GLTFDracoMeshCompressionExtension {
  constructor(json, dracoLoader) {
    if (!dracoLoader) {
      throw new Error('THREE.GLTFLoader: No DRACOLoader instance provided.');
    }

    this.name = EXTENSIONS.KHR_DRACO_MESH_COMPRESSION;
    this.json = json;
    this.dracoLoader = dracoLoader;
    this.dracoLoader.preload();
  }

  decodePrimitive(primitive, parser) {
    const json = this.json;
    const dracoLoader = this.dracoLoader;
    const bufferViewIndex = primitive.extensions[this.name].bufferView;
    const gltfAttributeMap = primitive.extensions[this.name].attributes;
    const threeAttributeMap = {};
    const attributeNormalizedMap = {};
    const attributeTypeMap = {};

    for (const attributeName in gltfAttributeMap) {
      const threeAttributeName = ATTRIBUTES[attributeName] || attributeName.toLowerCase();
      threeAttributeMap[threeAttributeName] = gltfAttributeMap[attributeName];
    }

    for (const attributeName in primitive.attributes) {
      const threeAttributeName = ATTRIBUTES[attributeName] || attributeName.toLowerCase();

      if (gltfAttributeMap[attributeName] !== undefined) {
        const accessorDef = json.accessors[primitive.attributes[attributeName]];
        const componentType = WEBGL_COMPONENT_TYPES[accessorDef.componentType];
        attributeTypeMap[threeAttributeName] = componentType;
        attributeNormalizedMap[threeAttributeName] = accessorDef.normalized === true;
      }
    }

    return parser.getDependency('bufferView', bufferViewIndex).then(function (bufferView) {
      return new Promise(function (resolve) {
        dracoLoader.decodeDracoFile(bufferView, function (geometry) {
          for (const attributeName in geometry.attributes) {
            const attribute = geometry.attributes[attributeName];
            const normalized = attributeNormalizedMap[attributeName];
            if (normalized !== undefined) attribute.normalized = normalized;
          }

          resolve(geometry);
        }, threeAttributeMap, attributeTypeMap);
      });
    });
  }

}
/**
 * THREE.Texture Transform Extension
 *
 * Specification: https://github.com/KhronosGroup/glTF/tree/master/extensions/2.0/Khronos/KHR_texture_transform
 */


class GLTFTextureTransformExtension {
  constructor() {
    this.name = EXTENSIONS.KHR_TEXTURE_TRANSFORM;
  }

  extendTexture(texture, transform) {
    if (transform.texCoord !== undefined) {
      console.warn('THREE.GLTFLoader: Custom UV sets in "' + this.name + '" extension not yet supported.');
    }

    if (transform.offset === undefined && transform.rotation === undefined && transform.scale === undefined) {
      // See https://github.com/mrdoob/three.js/issues/21819.
      return texture;
    }

    texture = texture.clone();

    if (transform.offset !== undefined) {
      texture.offset.fromArray(transform.offset);
    }

    if (transform.rotation !== undefined) {
      texture.rotation = transform.rotation;
    }

    if (transform.scale !== undefined) {
      texture.repeat.fromArray(transform.scale);
    }

    texture.needsUpdate = true;
    return texture;
  }

}
/**
 * Specular-Glossiness Extension
 *
 * Specification: https://github.com/KhronosGroup/glTF/tree/master/extensions/2.0/Khronos/KHR_materials_pbrSpecularGlossiness
 */

/**
 * A sub class of StandardMaterial with some of the functionality
 * changed via the `onBeforeCompile` callback
 * @pailhead
 */


class GLTFMeshStandardSGMaterial extends THREE.MeshStandardMaterial {
  constructor(params) {
    super();
    this.isGLTFSpecularGlossinessMaterial = true; //various chunks that need replacing

    const specularMapParsFragmentChunk = ['#ifdef USE_SPECULARMAP', '	uniform sampler2D specularMap;', '#endif'].join('\n');
    const glossinessMapParsFragmentChunk = ['#ifdef USE_GLOSSINESSMAP', '	uniform sampler2D glossinessMap;', '#endif'].join('\n');
    const specularMapFragmentChunk = ['vec3 specularFactor = specular;', '#ifdef USE_SPECULARMAP', '	vec4 texelSpecular = texture2D( specularMap, vUv );', '	texelSpecular = sRGBToLinear( texelSpecular );', '	// reads channel RGB, compatible with a glTF Specular-Glossiness (RGBA) texture', '	specularFactor *= texelSpecular.rgb;', '#endif'].join('\n');
    const glossinessMapFragmentChunk = ['float glossinessFactor = glossiness;', '#ifdef USE_GLOSSINESSMAP', '	vec4 texelGlossiness = texture2D( glossinessMap, vUv );', '	// reads channel A, compatible with a glTF Specular-Glossiness (RGBA) texture', '	glossinessFactor *= texelGlossiness.a;', '#endif'].join('\n');
    const lightPhysicalFragmentChunk = ['PhysicalMaterial material;', 'material.diffuseColor = diffuseColor.rgb * ( 1. - max( specularFactor.r, max( specularFactor.g, specularFactor.b ) ) );', 'vec3 dxy = max( abs( dFdx( geometryNormal ) ), abs( dFdy( geometryNormal ) ) );', 'float geometryRoughness = max( max( dxy.x, dxy.y ), dxy.z );', 'material.specularRoughness = max( 1.0 - glossinessFactor, 0.0525 ); // 0.0525 corresponds to the base mip of a 256 cubemap.', 'material.specularRoughness += geometryRoughness;', 'material.specularRoughness = min( material.specularRoughness, 1.0 );', 'material.specularColor = specularFactor;'].join('\n');
    const uniforms = {
      specular: {
        value: new THREE.Color().setHex(0xffffff)
      },
      glossiness: {
        value: 1
      },
      specularMap: {
        value: null
      },
      glossinessMap: {
        value: null
      }
    };
    this._extraUniforms = uniforms;

    this.onBeforeCompile = function (shader) {
      for (const uniformName in uniforms) {
        shader.uniforms[uniformName] = uniforms[uniformName];
      }

      shader.fragmentShader = shader.fragmentShader.replace('uniform float roughness;', 'uniform vec3 specular;').replace('uniform float metalness;', 'uniform float glossiness;').replace('#include <roughnessmap_pars_fragment>', specularMapParsFragmentChunk).replace('#include <metalnessmap_pars_fragment>', glossinessMapParsFragmentChunk).replace('#include <roughnessmap_fragment>', specularMapFragmentChunk).replace('#include <metalnessmap_fragment>', glossinessMapFragmentChunk).replace('#include <lights_physical_fragment>', lightPhysicalFragmentChunk);
    };

    Object.defineProperties(this, {
      specular: {
        get: function () {
          return uniforms.specular.value;
        },
        set: function (v) {
          uniforms.specular.value = v;
        }
      },
      specularMap: {
        get: function () {
          return uniforms.specularMap.value;
        },
        set: function (v) {
          uniforms.specularMap.value = v;

          if (v) {
            this.defines.USE_SPECULARMAP = ''; // USE_UV is set by the renderer for specular maps
          } else {
            delete this.defines.USE_SPECULARMAP;
          }
        }
      },
      glossiness: {
        get: function () {
          return uniforms.glossiness.value;
        },
        set: function (v) {
          uniforms.glossiness.value = v;
        }
      },
      glossinessMap: {
        get: function () {
          return uniforms.glossinessMap.value;
        },
        set: function (v) {
          uniforms.glossinessMap.value = v;

          if (v) {
            this.defines.USE_GLOSSINESSMAP = '';
            this.defines.USE_UV = '';
          } else {
            delete this.defines.USE_GLOSSINESSMAP;
            delete this.defines.USE_UV;
          }
        }
      }
    });
    delete this.metalness;
    delete this.roughness;
    delete this.metalnessMap;
    delete this.roughnessMap;
    this.setValues(params);
  }

  copy(source) {
    super.copy(source);
    this.specularMap = source.specularMap;
    this.specular.copy(source.specular);
    this.glossinessMap = source.glossinessMap;
    this.glossiness = source.glossiness;
    delete this.metalness;
    delete this.roughness;
    delete this.metalnessMap;
    delete this.roughnessMap;
    return this;
  }

}

class GLTFMaterialsPbrSpecularGlossinessExtension {
  constructor() {
    this.name = EXTENSIONS.KHR_MATERIALS_PBR_SPECULAR_GLOSSINESS;
    this.specularGlossinessParams = ['color', 'map', 'lightMap', 'lightMapIntensity', 'aoMap', 'aoMapIntensity', 'emissive', 'emissiveIntensity', 'emissiveMap', 'bumpMap', 'bumpScale', 'normalMap', 'normalMapType', 'displacementMap', 'displacementScale', 'displacementBias', 'specularMap', 'specular', 'glossinessMap', 'glossiness', 'alphaMap', 'envMap', 'envMapIntensity', 'refractionRatio'];
  }

  getMaterialType() {
    return GLTFMeshStandardSGMaterial;
  }

  extendParams(materialParams, materialDef, parser) {
    const pbrSpecularGlossiness = materialDef.extensions[this.name];
    materialParams.color = new THREE.Color(1.0, 1.0, 1.0);
    materialParams.opacity = 1.0;
    const pending = [];

    if (Array.isArray(pbrSpecularGlossiness.diffuseFactor)) {
      const array = pbrSpecularGlossiness.diffuseFactor;
      materialParams.color.fromArray(array);
      materialParams.opacity = array[3];
    }

    if (pbrSpecularGlossiness.diffuseTexture !== undefined) {
      pending.push(parser.assignTexture(materialParams, 'map', pbrSpecularGlossiness.diffuseTexture));
    }

    materialParams.emissive = new THREE.Color(0.0, 0.0, 0.0);
    materialParams.glossiness = pbrSpecularGlossiness.glossinessFactor !== undefined ? pbrSpecularGlossiness.glossinessFactor : 1.0;
    materialParams.specular = new THREE.Color(1.0, 1.0, 1.0);

    if (Array.isArray(pbrSpecularGlossiness.specularFactor)) {
      materialParams.specular.fromArray(pbrSpecularGlossiness.specularFactor);
    }

    if (pbrSpecularGlossiness.specularGlossinessTexture !== undefined) {
      const specGlossMapDef = pbrSpecularGlossiness.specularGlossinessTexture;
      pending.push(parser.assignTexture(materialParams, 'glossinessMap', specGlossMapDef));
      pending.push(parser.assignTexture(materialParams, 'specularMap', specGlossMapDef));
    }

    return Promise.all(pending);
  }

  createMaterial(materialParams) {
    const material = new GLTFMeshStandardSGMaterial(materialParams);
    material.fog = true;
    material.color = materialParams.color;
    material.map = materialParams.map === undefined ? null : materialParams.map;
    material.lightMap = null;
    material.lightMapIntensity = 1.0;
    material.aoMap = materialParams.aoMap === undefined ? null : materialParams.aoMap;
    material.aoMapIntensity = 1.0;
    material.emissive = materialParams.emissive;
    material.emissiveIntensity = 1.0;
    material.emissiveMap = materialParams.emissiveMap === undefined ? null : materialParams.emissiveMap;
    material.bumpMap = materialParams.bumpMap === undefined ? null : materialParams.bumpMap;
    material.bumpScale = 1;
    material.normalMap = materialParams.normalMap === undefined ? null : materialParams.normalMap;
    material.normalMapType = THREE.TangentSpaceNormalMap;
    if (materialParams.normalScale) material.normalScale = materialParams.normalScale;
    material.displacementMap = null;
    material.displacementScale = 1;
    material.displacementBias = 0;
    material.specularMap = materialParams.specularMap === undefined ? null : materialParams.specularMap;
    material.specular = materialParams.specular;
    material.glossinessMap = materialParams.glossinessMap === undefined ? null : materialParams.glossinessMap;
    material.glossiness = materialParams.glossiness;
    material.alphaMap = null;
    material.envMap = materialParams.envMap === undefined ? null : materialParams.envMap;
    material.envMapIntensity = 1.0;
    material.refractionRatio = 0.98;
    return material;
  }

}
/**
 * THREE.Mesh Quantization Extension
 *
 * Specification: https://github.com/KhronosGroup/glTF/tree/master/extensions/2.0/Khronos/KHR_mesh_quantization
 */


class GLTFMeshQuantizationExtension {
  constructor() {
    this.name = EXTENSIONS.KHR_MESH_QUANTIZATION;
  }

}
/*********************************/

/********** INTERPOLATION ********/

/*********************************/
// Spline Interpolation
// Specification: https://github.com/KhronosGroup/glTF/blob/master/specification/2.0/README.md#appendix-c-spline-interpolation


class GLTFCubicSplineInterpolant extends THREE.Interpolant {
  constructor(parameterPositions, sampleValues, sampleSize, resultBuffer) {
    super(parameterPositions, sampleValues, sampleSize, resultBuffer);
  }

  copySampleValue_(index) {
    // Copies a sample value to the result buffer. See description of glTF
    // CUBICSPLINE values layout in interpolate_() function below.
    const result = this.resultBuffer,
          values = this.sampleValues,
          valueSize = this.valueSize,
          offset = index * valueSize * 3 + valueSize;

    for (let i = 0; i !== valueSize; i++) {
      result[i] = values[offset + i];
    }

    return result;
  }

}

GLTFCubicSplineInterpolant.prototype.beforeStart_ = GLTFCubicSplineInterpolant.prototype.copySampleValue_;
GLTFCubicSplineInterpolant.prototype.afterEnd_ = GLTFCubicSplineInterpolant.prototype.copySampleValue_;

GLTFCubicSplineInterpolant.prototype.interpolate_ = function (i1, t0, t, t1) {
  const result = this.resultBuffer;
  const values = this.sampleValues;
  const stride = this.valueSize;
  const stride2 = stride * 2;
  const stride3 = stride * 3;
  const td = t1 - t0;
  const p = (t - t0) / td;
  const pp = p * p;
  const ppp = pp * p;
  const offset1 = i1 * stride3;
  const offset0 = offset1 - stride3;
  const s2 = -2 * ppp + 3 * pp;
  const s3 = ppp - pp;
  const s0 = 1 - s2;
  const s1 = s3 - pp + p; // Layout of keyframe output values for CUBICSPLINE animations:
  //   [ inTangent_1, splineVertex_1, outTangent_1, inTangent_2, splineVertex_2, ... ]

  for (let i = 0; i !== stride; i++) {
    const p0 = values[offset0 + i + stride]; // splineVertex_k

    const m0 = values[offset0 + i + stride2] * td; // outTangent_k * (t_k+1 - t_k)

    const p1 = values[offset1 + i + stride]; // splineVertex_k+1

    const m1 = values[offset1 + i] * td; // inTangent_k+1 * (t_k+1 - t_k)

    result[i] = s0 * p0 + s1 * m0 + s2 * p1 + s3 * m1;
  }

  return result;
};
/*********************************/

/********** INTERNALS ************/

/*********************************/

/* CONSTANTS */


const WEBGL_CONSTANTS = {
  FLOAT: 5126,
  //FLOAT_MAT2: 35674,
  FLOAT_MAT3: 35675,
  FLOAT_MAT4: 35676,
  FLOAT_VEC2: 35664,
  FLOAT_VEC3: 35665,
  FLOAT_VEC4: 35666,
  LINEAR: 9729,
  REPEAT: 10497,
  SAMPLER_2D: 35678,
  POINTS: 0,
  LINES: 1,
  LINE_LOOP: 2,
  LINE_STRIP: 3,
  TRIANGLES: 4,
  TRIANGLE_STRIP: 5,
  TRIANGLE_FAN: 6,
  UNSIGNED_BYTE: 5121,
  UNSIGNED_SHORT: 5123
};
const WEBGL_COMPONENT_TYPES = {
  5120: Int8Array,
  5121: Uint8Array,
  5122: Int16Array,
  5123: Uint16Array,
  5125: Uint32Array,
  5126: Float32Array
};
const WEBGL_FILTERS = {
  9728: THREE.NearestFilter,
  9729: THREE.LinearFilter,
  9984: THREE.NearestMipmapNearestFilter,
  9985: THREE.LinearMipmapNearestFilter,
  9986: THREE.NearestMipmapLinearFilter,
  9987: THREE.LinearMipmapLinearFilter
};
const WEBGL_WRAPPINGS = {
  33071: THREE.ClampToEdgeWrapping,
  33648: THREE.MirroredRepeatWrapping,
  10497: THREE.RepeatWrapping
};
const WEBGL_TYPE_SIZES = {
  'SCALAR': 1,
  'VEC2': 2,
  'VEC3': 3,
  'VEC4': 4,
  'MAT2': 4,
  'MAT3': 9,
  'MAT4': 16
};
const ATTRIBUTES = {
  POSITION: 'position',
  NORMAL: 'normal',
  TANGENT: 'tangent',
  TEXCOORD_0: 'uv',
  TEXCOORD_1: 'uv2',
  COLOR_0: 'color',
  WEIGHTS_0: 'skinWeight',
  JOINTS_0: 'skinIndex'
};
const PATH_PROPERTIES = {
  scale: 'scale',
  translation: 'position',
  rotation: 'quaternion',
  weights: 'morphTargetInfluences'
};
const INTERPOLATION = {
  CUBICSPLINE: undefined,
  // We use a custom interpolant (GLTFCubicSplineInterpolation) for CUBICSPLINE tracks. Each
  // keyframe track will be initialized with a default interpolation type, then modified.
  LINEAR: THREE.InterpolateLinear,
  STEP: THREE.InterpolateDiscrete
};
const ALPHA_MODES = {
  OPAQUE: 'OPAQUE',
  MASK: 'MASK',
  BLEND: 'BLEND'
};
/* UTILITY FUNCTIONS */

function resolveURL(url, path) {
  // Invalid URL
  if (typeof url !== 'string' || url === '') return ''; // Host Relative URL

  if (/^https?:\/\//i.test(path) && /^\//.test(url)) {
    path = path.replace(/(^https?:\/\/[^\/]+).*/i, '$1');
  } // Absolute URL http://,https://,//


  if (/^(https?:)?\/\//i.test(url)) return url; // Data URI

  if (/^data:.*,.*$/i.test(url)) return url; // Blob URL

  if (/^blob:.*$/i.test(url)) return url; // Relative URL

  return path + url;
}
/**
 * Specification: https://github.com/KhronosGroup/glTF/blob/master/specification/2.0/README.md#default-material
 */


function createDefaultMaterial(cache) {
  if (cache['DefaultMaterial'] === undefined) {
    cache['DefaultMaterial'] = new THREE.MeshStandardMaterial({
      color: 0xFFFFFF,
      emissive: 0x000000,
      metalness: 1,
      roughness: 1,
      transparent: false,
      depthTest: true,
      side: THREE.FrontSide
    });
  }

  return cache['DefaultMaterial'];
}

function addUnknownExtensionsToUserData(knownExtensions, object, objectDef) {
  // Add unknown glTF extensions to an object's userData.
  for (const name in objectDef.extensions) {
    if (knownExtensions[name] === undefined) {
      object.userData.gltfExtensions = object.userData.gltfExtensions || {};
      object.userData.gltfExtensions[name] = objectDef.extensions[name];
    }
  }
}
/**
 * @param {Object3D|Material|BufferGeometry} object
 * @param {GLTF.definition} gltfDef
 */


function assignExtrasToUserData(object, gltfDef) {
  if (gltfDef.extras !== undefined) {
    if (typeof gltfDef.extras === 'object') {
      Object.assign(object.userData, gltfDef.extras);
    } else {
      console.warn('THREE.GLTFLoader: Ignoring primitive type .extras, ' + gltfDef.extras);
    }
  }
}
/**
 * Specification: https://github.com/KhronosGroup/glTF/blob/master/specification/2.0/README.md#morph-targets
 *
 * @param {BufferGeometry} geometry
 * @param {Array<GLTF.Target>} targets
 * @param {GLTFParser} parser
 * @return {Promise<BufferGeometry>}
 */


function addMorphTargets(geometry, targets, parser) {
  let hasMorphPosition = false;
  let hasMorphNormal = false;

  for (let i = 0, il = targets.length; i < il; i++) {
    const target = targets[i];
    if (target.POSITION !== undefined) hasMorphPosition = true;
    if (target.NORMAL !== undefined) hasMorphNormal = true;
    if (hasMorphPosition && hasMorphNormal) break;
  }

  if (!hasMorphPosition && !hasMorphNormal) return Promise.resolve(geometry);
  const pendingPositionAccessors = [];
  const pendingNormalAccessors = [];

  for (let i = 0, il = targets.length; i < il; i++) {
    const target = targets[i];

    if (hasMorphPosition) {
      const pendingAccessor = target.POSITION !== undefined ? parser.getDependency('accessor', target.POSITION) : geometry.attributes.position;
      pendingPositionAccessors.push(pendingAccessor);
    }

    if (hasMorphNormal) {
      const pendingAccessor = target.NORMAL !== undefined ? parser.getDependency('accessor', target.NORMAL) : geometry.attributes.normal;
      pendingNormalAccessors.push(pendingAccessor);
    }
  }

  return Promise.all([Promise.all(pendingPositionAccessors), Promise.all(pendingNormalAccessors)]).then(function (accessors) {
    const morphPositions = accessors[0];
    const morphNormals = accessors[1];
    if (hasMorphPosition) geometry.morphAttributes.position = morphPositions;
    if (hasMorphNormal) geometry.morphAttributes.normal = morphNormals;
    geometry.morphTargetsRelative = true;
    return geometry;
  });
}
/**
 * @param {Mesh} mesh
 * @param {GLTF.Mesh} meshDef
 */


function updateMorphTargets(mesh, meshDef) {
  mesh.updateMorphTargets();

  if (meshDef.weights !== undefined) {
    for (let i = 0, il = meshDef.weights.length; i < il; i++) {
      mesh.morphTargetInfluences[i] = meshDef.weights[i];
    }
  } // .extras has user-defined data, so check that .extras.targetNames is an array.


  if (meshDef.extras && Array.isArray(meshDef.extras.targetNames)) {
    const targetNames = meshDef.extras.targetNames;

    if (mesh.morphTargetInfluences.length === targetNames.length) {
      mesh.morphTargetDictionary = {};

      for (let i = 0, il = targetNames.length; i < il; i++) {
        mesh.morphTargetDictionary[targetNames[i]] = i;
      }
    } else {
      console.warn('THREE.GLTFLoader: Invalid extras.targetNames length. Ignoring names.');
    }
  }
}

function createPrimitiveKey(primitiveDef) {
  const dracoExtension = primitiveDef.extensions && primitiveDef.extensions[EXTENSIONS.KHR_DRACO_MESH_COMPRESSION];
  let geometryKey;

  if (dracoExtension) {
    geometryKey = 'draco:' + dracoExtension.bufferView + ':' + dracoExtension.indices + ':' + createAttributesKey(dracoExtension.attributes);
  } else {
    geometryKey = primitiveDef.indices + ':' + createAttributesKey(primitiveDef.attributes) + ':' + primitiveDef.mode;
  }

  return geometryKey;
}

function createAttributesKey(attributes) {
  let attributesKey = '';
  const keys = Object.keys(attributes).sort();

  for (let i = 0, il = keys.length; i < il; i++) {
    attributesKey += keys[i] + ':' + attributes[keys[i]] + ';';
  }

  return attributesKey;
}

function getNormalizedComponentScale(constructor) {
  // Reference:
  // https://github.com/KhronosGroup/glTF/tree/master/extensions/2.0/Khronos/KHR_mesh_quantization#encoding-quantized-data
  switch (constructor) {
    case Int8Array:
      return 1 / 127;

    case Uint8Array:
      return 1 / 255;

    case Int16Array:
      return 1 / 32767;

    case Uint16Array:
      return 1 / 65535;

    default:
      throw new Error('THREE.GLTFLoader: Unsupported normalized accessor component type.');
  }
}
/* GLTF PARSER */


class GLTFParser {
  constructor(json = {}, options = {}) {
    this.json = json;
    this.extensions = {};
    this.plugins = {};
    this.options = options; // loader object cache

    this.cache = new GLTFRegistry(); // associations between Three.js objects and glTF elements

    this.associations = new Map(); // THREE.BufferGeometry caching

    this.primitiveCache = {}; // THREE.Object3D instance caches

    this.meshCache = {
      refs: {},
      uses: {}
    };
    this.cameraCache = {
      refs: {},
      uses: {}
    };
    this.lightCache = {
      refs: {},
      uses: {}
    };
    this.textureCache = {}; // Track node names, to ensure no duplicates

    this.nodeNamesUsed = {}; // Use an THREE.ImageBitmapLoader if imageBitmaps are supported. Moves much of the
    // expensive work of uploading a texture to the GPU off the main thread.

    if (typeof createImageBitmap !== 'undefined' && /Firefox/.test(navigator.userAgent) === false) {
      this.textureLoader = new THREE.ImageBitmapLoader(this.options.manager);
    } else {
      this.textureLoader = new THREE.TextureLoader(this.options.manager);
    }

    this.textureLoader.setCrossOrigin(this.options.crossOrigin);
    this.textureLoader.setRequestHeader(this.options.requestHeader);
    this.fileLoader = new THREE.FileLoader(this.options.manager);
    this.fileLoader.setResponseType('arraybuffer');

    if (this.options.crossOrigin === 'use-credentials') {
      this.fileLoader.setWithCredentials(true);
    }
  }

  setExtensions(extensions) {
    this.extensions = extensions;
  }

  setPlugins(plugins) {
    this.plugins = plugins;
  }

  parse(onLoad, onError) {
    const parser = this;
    const json = this.json;
    const extensions = this.extensions; // Clear the loader cache

    this.cache.removeAll(); // Mark the special nodes/meshes in json for efficient parse

    this._invokeAll(function (ext) {
      return ext._markDefs && ext._markDefs();
    });

    Promise.all(this._invokeAll(function (ext) {
      return ext.beforeRoot && ext.beforeRoot();
    })).then(function () {
      return Promise.all([parser.getDependencies('scene'), parser.getDependencies('animation'), parser.getDependencies('camera')]);
    }).then(function (dependencies) {
      const result = {
        scene: dependencies[0][json.scene || 0],
        scenes: dependencies[0],
        animations: dependencies[1],
        cameras: dependencies[2],
        asset: json.asset,
        parser: parser,
        userData: {}
      };
      addUnknownExtensionsToUserData(extensions, result, json);
      assignExtrasToUserData(result, json);
      Promise.all(parser._invokeAll(function (ext) {
        return ext.afterRoot && ext.afterRoot(result);
      })).then(function () {
        onLoad(result);
      });
    }).catch(onError);
  }
  /**
   * Marks the special nodes/meshes in json for efficient parse.
   */


  _markDefs() {
    const nodeDefs = this.json.nodes || [];
    const skinDefs = this.json.skins || [];
    const meshDefs = this.json.meshes || []; // Nothing in the node definition indicates whether it is a THREE.Bone or an
    // THREE.Object3D. Use the skins' joint references to mark bones.

    for (let skinIndex = 0, skinLength = skinDefs.length; skinIndex < skinLength; skinIndex++) {
      const joints = skinDefs[skinIndex].joints;

      for (let i = 0, il = joints.length; i < il; i++) {
        nodeDefs[joints[i]].isBone = true;
      }
    } // Iterate over all nodes, marking references to shared resources,
    // as well as skeleton joints.


    for (let nodeIndex = 0, nodeLength = nodeDefs.length; nodeIndex < nodeLength; nodeIndex++) {
      const nodeDef = nodeDefs[nodeIndex];

      if (nodeDef.mesh !== undefined) {
        this._addNodeRef(this.meshCache, nodeDef.mesh); // Nothing in the mesh definition indicates whether it is
        // a THREE.SkinnedMesh or THREE.Mesh. Use the node's mesh reference
        // to mark THREE.SkinnedMesh if node has skin.


        if (nodeDef.skin !== undefined) {
          meshDefs[nodeDef.mesh].isSkinnedMesh = true;
        }
      }

      if (nodeDef.camera !== undefined) {
        this._addNodeRef(this.cameraCache, nodeDef.camera);
      }
    }
  }
  /**
   * Counts references to shared node / THREE.Object3D resources. These resources
   * can be reused, or "instantiated", at multiple nodes in the scene
   * hierarchy. THREE.Mesh, Camera, and Light instances are instantiated and must
   * be marked. Non-scenegraph resources (like Materials, Geometries, and
   * Textures) can be reused directly and are not marked here.
   *
   * Example: CesiumMilkTruck sample model reuses "Wheel" meshes.
   */


  _addNodeRef(cache, index) {
    if (index === undefined) return;

    if (cache.refs[index] === undefined) {
      cache.refs[index] = cache.uses[index] = 0;
    }

    cache.refs[index]++;
  }
  /** Returns a reference to a shared resource, cloning it if necessary. */


  _getNodeRef(cache, index, object) {
    if (cache.refs[index] <= 1) return object;
    const ref = object.clone();
    ref.name += '_instance_' + cache.uses[index]++;
    return ref;
  }

  _invokeOne(func) {
    const extensions = Object.values(this.plugins);
    extensions.push(this);

    for (let i = 0; i < extensions.length; i++) {
      const result = func(extensions[i]);
      if (result) return result;
    }

    return null;
  }

  _invokeAll(func) {
    const extensions = Object.values(this.plugins);
    extensions.unshift(this);
    const pending = [];

    for (let i = 0; i < extensions.length; i++) {
      const result = func(extensions[i]);
      if (result) pending.push(result);
    }

    return pending;
  }
  /**
   * Requests the specified dependency asynchronously, with caching.
   * @param {string} type
   * @param {number} index
   * @return {Promise<Object3D|Material|THREE.Texture|AnimationClip|ArrayBuffer|Object>}
   */


  getDependency(type, index) {
    const cacheKey = type + ':' + index;
    let dependency = this.cache.get(cacheKey);

    if (!dependency) {
      switch (type) {
        case 'scene':
          dependency = this.loadScene(index);
          break;

        case 'node':
          dependency = this.loadNode(index);
          break;

        case 'mesh':
          dependency = this._invokeOne(function (ext) {
            return ext.loadMesh && ext.loadMesh(index);
          });
          break;

        case 'accessor':
          dependency = this.loadAccessor(index);
          break;

        case 'bufferView':
          dependency = this._invokeOne(function (ext) {
            return ext.loadBufferView && ext.loadBufferView(index);
          });
          break;

        case 'buffer':
          dependency = this.loadBuffer(index);
          break;

        case 'material':
          dependency = this._invokeOne(function (ext) {
            return ext.loadMaterial && ext.loadMaterial(index);
          });
          break;

        case 'texture':
          dependency = this._invokeOne(function (ext) {
            return ext.loadTexture && ext.loadTexture(index);
          });
          break;

        case 'skin':
          dependency = this.loadSkin(index);
          break;

        case 'animation':
          dependency = this.loadAnimation(index);
          break;

        case 'camera':
          dependency = this.loadCamera(index);
          break;

        default:
          throw new Error('Unknown type: ' + type);
      }

      this.cache.add(cacheKey, dependency);
    }

    return dependency;
  }
  /**
   * Requests all dependencies of the specified type asynchronously, with caching.
   * @param {string} type
   * @return {Promise<Array<Object>>}
   */


  getDependencies(type) {
    let dependencies = this.cache.get(type);

    if (!dependencies) {
      const parser = this;
      const defs = this.json[type + (type === 'mesh' ? 'es' : 's')] || [];
      dependencies = Promise.all(defs.map(function (def, index) {
        return parser.getDependency(type, index);
      }));
      this.cache.add(type, dependencies);
    }

    return dependencies;
  }
  /**
   * Specification: https://github.com/KhronosGroup/glTF/blob/master/specification/2.0/README.md#buffers-and-buffer-views
   * @param {number} bufferIndex
   * @return {Promise<ArrayBuffer>}
   */


  loadBuffer(bufferIndex) {
    const bufferDef = this.json.buffers[bufferIndex];
    const loader = this.fileLoader;

    if (bufferDef.type && bufferDef.type !== 'arraybuffer') {
      throw new Error('THREE.GLTFLoader: ' + bufferDef.type + ' buffer type is not supported.');
    } // If present, GLB container is required to be the first buffer.


    if (bufferDef.uri === undefined && bufferIndex === 0) {
      return Promise.resolve(this.extensions[EXTENSIONS.KHR_BINARY_GLTF].body);
    }

    const options = this.options;
    return new Promise(function (resolve, reject) {
      loader.load(resolveURL(bufferDef.uri, options.path), resolve, undefined, function () {
        reject(new Error('THREE.GLTFLoader: Failed to load buffer "' + bufferDef.uri + '".'));
      });
    });
  }
  /**
   * Specification: https://github.com/KhronosGroup/glTF/blob/master/specification/2.0/README.md#buffers-and-buffer-views
   * @param {number} bufferViewIndex
   * @return {Promise<ArrayBuffer>}
   */


  loadBufferView(bufferViewIndex) {
    const bufferViewDef = this.json.bufferViews[bufferViewIndex];
    return this.getDependency('buffer', bufferViewDef.buffer).then(function (buffer) {
      const byteLength = bufferViewDef.byteLength || 0;
      const byteOffset = bufferViewDef.byteOffset || 0;
      return buffer.slice(byteOffset, byteOffset + byteLength);
    });
  }
  /**
   * Specification: https://github.com/KhronosGroup/glTF/blob/master/specification/2.0/README.md#accessors
   * @param {number} accessorIndex
   * @return {Promise<BufferAttribute|InterleavedBufferAttribute>}
   */


  loadAccessor(accessorIndex) {
    const parser = this;
    const json = this.json;
    const accessorDef = this.json.accessors[accessorIndex];

    if (accessorDef.bufferView === undefined && accessorDef.sparse === undefined) {
      // Ignore empty accessors, which may be used to declare runtime
      // information about attributes coming from another source (e.g. Draco
      // compression extension).
      return Promise.resolve(null);
    }

    const pendingBufferViews = [];

    if (accessorDef.bufferView !== undefined) {
      pendingBufferViews.push(this.getDependency('bufferView', accessorDef.bufferView));
    } else {
      pendingBufferViews.push(null);
    }

    if (accessorDef.sparse !== undefined) {
      pendingBufferViews.push(this.getDependency('bufferView', accessorDef.sparse.indices.bufferView));
      pendingBufferViews.push(this.getDependency('bufferView', accessorDef.sparse.values.bufferView));
    }

    return Promise.all(pendingBufferViews).then(function (bufferViews) {
      const bufferView = bufferViews[0];
      const itemSize = WEBGL_TYPE_SIZES[accessorDef.type];
      const TypedArray = WEBGL_COMPONENT_TYPES[accessorDef.componentType]; // For VEC3: itemSize is 3, elementBytes is 4, itemBytes is 12.

      const elementBytes = TypedArray.BYTES_PER_ELEMENT;
      const itemBytes = elementBytes * itemSize;
      const byteOffset = accessorDef.byteOffset || 0;
      const byteStride = accessorDef.bufferView !== undefined ? json.bufferViews[accessorDef.bufferView].byteStride : undefined;
      const normalized = accessorDef.normalized === true;
      let array, bufferAttribute; // The buffer is not interleaved if the stride is the item size in bytes.

      if (byteStride && byteStride !== itemBytes) {
        // Each "slice" of the buffer, as defined by 'count' elements of 'byteStride' bytes, gets its own THREE.InterleavedBuffer
        // This makes sure that IBA.count reflects accessor.count properly
        const ibSlice = Math.floor(byteOffset / byteStride);
        const ibCacheKey = 'InterleavedBuffer:' + accessorDef.bufferView + ':' + accessorDef.componentType + ':' + ibSlice + ':' + accessorDef.count;
        let ib = parser.cache.get(ibCacheKey);

        if (!ib) {
          array = new TypedArray(bufferView, ibSlice * byteStride, accessorDef.count * byteStride / elementBytes); // Integer parameters to IB/IBA are in array elements, not bytes.

          ib = new THREE.InterleavedBuffer(array, byteStride / elementBytes);
          parser.cache.add(ibCacheKey, ib);
        }

        bufferAttribute = new THREE.InterleavedBufferAttribute(ib, itemSize, byteOffset % byteStride / elementBytes, normalized);
      } else {
        if (bufferView === null) {
          array = new TypedArray(accessorDef.count * itemSize);
        } else {
          array = new TypedArray(bufferView, byteOffset, accessorDef.count * itemSize);
        }

        bufferAttribute = new THREE.BufferAttribute(array, itemSize, normalized);
      } // https://github.com/KhronosGroup/glTF/blob/master/specification/2.0/README.md#sparse-accessors


      if (accessorDef.sparse !== undefined) {
        const itemSizeIndices = WEBGL_TYPE_SIZES.SCALAR;
        const TypedArrayIndices = WEBGL_COMPONENT_TYPES[accessorDef.sparse.indices.componentType];
        const byteOffsetIndices = accessorDef.sparse.indices.byteOffset || 0;
        const byteOffsetValues = accessorDef.sparse.values.byteOffset || 0;
        const sparseIndices = new TypedArrayIndices(bufferViews[1], byteOffsetIndices, accessorDef.sparse.count * itemSizeIndices);
        const sparseValues = new TypedArray(bufferViews[2], byteOffsetValues, accessorDef.sparse.count * itemSize);

        if (bufferView !== null) {
          // Avoid modifying the original ArrayBuffer, if the bufferView wasn't initialized with zeroes.
          bufferAttribute = new THREE.BufferAttribute(bufferAttribute.array.slice(), bufferAttribute.itemSize, bufferAttribute.normalized);
        }

        for (let i = 0, il = sparseIndices.length; i < il; i++) {
          const index = sparseIndices[i];
          bufferAttribute.setX(index, sparseValues[i * itemSize]);
          if (itemSize >= 2) bufferAttribute.setY(index, sparseValues[i * itemSize + 1]);
          if (itemSize >= 3) bufferAttribute.setZ(index, sparseValues[i * itemSize + 2]);
          if (itemSize >= 4) bufferAttribute.setW(index, sparseValues[i * itemSize + 3]);
          if (itemSize >= 5) throw new Error('THREE.GLTFLoader: Unsupported itemSize in sparse THREE.BufferAttribute.');
        }
      }

      return bufferAttribute;
    });
  }
  /**
   * Specification: https://github.com/KhronosGroup/glTF/tree/master/specification/2.0#textures
   * @param {number} textureIndex
   * @return {Promise<THREE.Texture>}
   */


  loadTexture(textureIndex) {
    const json = this.json;
    const options = this.options;
    const textureDef = json.textures[textureIndex];
    const source = json.images[textureDef.source];
    let loader = this.textureLoader;

    if (source.uri) {
      const handler = options.manager.getHandler(source.uri);
      if (handler !== null) loader = handler;
    }

    return this.loadTextureImage(textureIndex, source, loader);
  }

  loadTextureImage(textureIndex, source, loader) {
    const parser = this;
    const json = this.json;
    const options = this.options;
    const textureDef = json.textures[textureIndex];
    const cacheKey = (source.uri || source.bufferView) + ':' + textureDef.sampler;

    if (this.textureCache[cacheKey]) {
      // See https://github.com/mrdoob/three.js/issues/21559.
      return this.textureCache[cacheKey];
    }

    const URL = self.URL || self.webkitURL;
    let sourceURI = source.uri || '';
    let isObjectURL = false;
    let hasAlpha = true;
    const isJPEG = sourceURI.search(/\.jpe?g($|\?)/i) > 0 || sourceURI.search(/^data\:image\/jpeg/) === 0;
    if (source.mimeType === 'image/jpeg' || isJPEG) hasAlpha = false;

    if (source.bufferView !== undefined) {
      // Load binary image data from bufferView, if provided.
      sourceURI = parser.getDependency('bufferView', source.bufferView).then(function (bufferView) {
        if (source.mimeType === 'image/png') {
          // Inspect the PNG 'IHDR' chunk to determine whether the image could have an
          // alpha channel. This check is conservative — the image could have an alpha
          // channel with all values == 1, and the indexed type (colorType == 3) only
          // sometimes contains alpha.
          //
          // https://en.wikipedia.org/wiki/Portable_Network_Graphics#File_header
          const colorType = new DataView(bufferView, 25, 1).getUint8(0, false);
          hasAlpha = colorType === 6 || colorType === 4 || colorType === 3;
        }

        isObjectURL = true;
        const blob = new Blob([bufferView], {
          type: source.mimeType
        });
        sourceURI = URL.createObjectURL(blob);
        return sourceURI;
      });
    } else if (source.uri === undefined) {
      throw new Error('THREE.GLTFLoader: Image ' + textureIndex + ' is missing URI and bufferView');
    }

    const promise = Promise.resolve(sourceURI).then(function (sourceURI) {
      return new Promise(function (resolve, reject) {
        let onLoad = resolve;

        if (loader.isImageBitmapLoader === true) {
          onLoad = function (imageBitmap) {
            const texture = new THREE.Texture(imageBitmap);
            texture.needsUpdate = true;
            resolve(texture);
          };
        }

        loader.load(resolveURL(sourceURI, options.path), onLoad, undefined, reject);
      });
    }).then(function (texture) {
      // Clean up resources and configure THREE.Texture.
      if (isObjectURL === true) {
        URL.revokeObjectURL(sourceURI);
      }

      texture.flipY = false;
      if (textureDef.name) texture.name = textureDef.name; // When there is definitely no alpha channel in the texture, set THREE.RGBFormat to save space.

      if (!hasAlpha) texture.format = THREE.RGBFormat;
      const samplers = json.samplers || {};
      const sampler = samplers[textureDef.sampler] || {};
      texture.magFilter = WEBGL_FILTERS[sampler.magFilter] || THREE.LinearFilter;
      texture.minFilter = WEBGL_FILTERS[sampler.minFilter] || THREE.LinearMipmapLinearFilter;
      texture.wrapS = WEBGL_WRAPPINGS[sampler.wrapS] || THREE.RepeatWrapping;
      texture.wrapT = WEBGL_WRAPPINGS[sampler.wrapT] || THREE.RepeatWrapping;
      parser.associations.set(texture, {
        type: 'textures',
        index: textureIndex
      });
      return texture;
    });
    this.textureCache[cacheKey] = promise;
    return promise;
  }
  /**
   * Asynchronously assigns a texture to the given material parameters.
   * @param {Object} materialParams
   * @param {string} mapName
   * @param {Object} mapDef
   * @return {Promise}
   */


  assignTexture(materialParams, mapName, mapDef) {
    const parser = this;
    return this.getDependency('texture', mapDef.index).then(function (texture) {
      // Materials sample aoMap from UV set 1 and other maps from UV set 0 - this can't be configured
      // However, we will copy UV set 0 to UV set 1 on demand for aoMap
      if (mapDef.texCoord !== undefined && mapDef.texCoord != 0 && !(mapName === 'aoMap' && mapDef.texCoord == 1)) {
        console.warn('THREE.GLTFLoader: Custom UV set ' + mapDef.texCoord + ' for texture ' + mapName + ' not yet supported.');
      }

      if (parser.extensions[EXTENSIONS.KHR_TEXTURE_TRANSFORM]) {
        const transform = mapDef.extensions !== undefined ? mapDef.extensions[EXTENSIONS.KHR_TEXTURE_TRANSFORM] : undefined;

        if (transform) {
          const gltfReference = parser.associations.get(texture);
          texture = parser.extensions[EXTENSIONS.KHR_TEXTURE_TRANSFORM].extendTexture(texture, transform);
          parser.associations.set(texture, gltfReference);
        }
      }

      materialParams[mapName] = texture;
    });
  }
  /**
   * Assigns final material to a THREE.Mesh, THREE.Line, or THREE.Points instance. The instance
   * already has a material (generated from the glTF material options alone)
   * but reuse of the same glTF material may require multiple threejs materials
   * to accommodate different primitive types, defines, etc. New materials will
   * be created if necessary, and reused from a cache.
   * @param  {Object3D} mesh THREE.Mesh, THREE.Line, or THREE.Points instance.
   */


  assignFinalMaterial(mesh) {
    const geometry = mesh.geometry;
    let material = mesh.material;
    const useVertexTangents = geometry.attributes.tangent !== undefined;
    const useVertexColors = geometry.attributes.color !== undefined;
    const useFlatShading = geometry.attributes.normal === undefined;
    const useMorphTargets = Object.keys(geometry.morphAttributes).length > 0;
    const useMorphNormals = useMorphTargets && geometry.morphAttributes.normal !== undefined;

    if (mesh.isPoints) {
      const cacheKey = 'PointsMaterial:' + material.uuid;
      let pointsMaterial = this.cache.get(cacheKey);

      if (!pointsMaterial) {
        pointsMaterial = new THREE.PointsMaterial();
        THREE.Material.prototype.copy.call(pointsMaterial, material);
        pointsMaterial.color.copy(material.color);
        pointsMaterial.map = material.map;
        pointsMaterial.sizeAttenuation = false; // glTF spec says points should be 1px

        this.cache.add(cacheKey, pointsMaterial);
      }

      material = pointsMaterial;
    } else if (mesh.isLine) {
      const cacheKey = 'LineBasicMaterial:' + material.uuid;
      let lineMaterial = this.cache.get(cacheKey);

      if (!lineMaterial) {
        lineMaterial = new THREE.LineBasicMaterial();
        THREE.Material.prototype.copy.call(lineMaterial, material);
        lineMaterial.color.copy(material.color);
        this.cache.add(cacheKey, lineMaterial);
      }

      material = lineMaterial;
    } // Clone the material if it will be modified


    if (useVertexTangents || useVertexColors || useFlatShading || useMorphTargets) {
      let cacheKey = 'ClonedMaterial:' + material.uuid + ':';
      if (material.isGLTFSpecularGlossinessMaterial) cacheKey += 'specular-glossiness:';
      if (useVertexTangents) cacheKey += 'vertex-tangents:';
      if (useVertexColors) cacheKey += 'vertex-colors:';
      if (useFlatShading) cacheKey += 'flat-shading:';
      if (useMorphTargets) cacheKey += 'morph-targets:';
      if (useMorphNormals) cacheKey += 'morph-normals:';
      let cachedMaterial = this.cache.get(cacheKey);

      if (!cachedMaterial) {
        cachedMaterial = material.clone();
        if (useVertexColors) cachedMaterial.vertexColors = true;
        if (useFlatShading) cachedMaterial.flatShading = true;
        if (useMorphTargets) cachedMaterial.morphTargets = true;
        if (useMorphNormals) cachedMaterial.morphNormals = true;

        if (useVertexTangents) {
          cachedMaterial.vertexTangents = true; // https://github.com/mrdoob/three.js/issues/11438#issuecomment-507003995

          if (cachedMaterial.normalScale) cachedMaterial.normalScale.y *= -1;
          if (cachedMaterial.clearcoatNormalScale) cachedMaterial.clearcoatNormalScale.y *= -1;
        }

        this.cache.add(cacheKey, cachedMaterial);
        this.associations.set(cachedMaterial, this.associations.get(material));
      }

      material = cachedMaterial;
    } // workarounds for mesh and geometry


    if (material.aoMap && geometry.attributes.uv2 === undefined && geometry.attributes.uv !== undefined) {
      geometry.setAttribute('uv2', geometry.attributes.uv);
    }

    mesh.material = material;
  }

  getMaterialType()
  /* materialIndex */
  {
    return THREE.MeshStandardMaterial;
  }
  /**
   * Specification: https://github.com/KhronosGroup/glTF/blob/master/specification/2.0/README.md#materials
   * @param {number} materialIndex
   * @return {Promise<Material>}
   */


  loadMaterial(materialIndex) {
    const parser = this;
    const json = this.json;
    const extensions = this.extensions;
    const materialDef = json.materials[materialIndex];
    let materialType;
    const materialParams = {};
    const materialExtensions = materialDef.extensions || {};
    const pending = [];

    if (materialExtensions[EXTENSIONS.KHR_MATERIALS_PBR_SPECULAR_GLOSSINESS]) {
      const sgExtension = extensions[EXTENSIONS.KHR_MATERIALS_PBR_SPECULAR_GLOSSINESS];
      materialType = sgExtension.getMaterialType();
      pending.push(sgExtension.extendParams(materialParams, materialDef, parser));
    } else if (materialExtensions[EXTENSIONS.KHR_MATERIALS_UNLIT]) {
      const kmuExtension = extensions[EXTENSIONS.KHR_MATERIALS_UNLIT];
      materialType = kmuExtension.getMaterialType();
      pending.push(kmuExtension.extendParams(materialParams, materialDef, parser));
    } else {
      // Specification:
      // https://github.com/KhronosGroup/glTF/tree/master/specification/2.0#metallic-roughness-material
      const metallicRoughness = materialDef.pbrMetallicRoughness || {};
      materialParams.color = new THREE.Color(1.0, 1.0, 1.0);
      materialParams.opacity = 1.0;

      if (Array.isArray(metallicRoughness.baseColorFactor)) {
        const array = metallicRoughness.baseColorFactor;
        materialParams.color.fromArray(array);
        materialParams.opacity = array[3];
      }

      if (metallicRoughness.baseColorTexture !== undefined) {
        pending.push(parser.assignTexture(materialParams, 'map', metallicRoughness.baseColorTexture));
      }

      materialParams.metalness = metallicRoughness.metallicFactor !== undefined ? metallicRoughness.metallicFactor : 1.0;
      materialParams.roughness = metallicRoughness.roughnessFactor !== undefined ? metallicRoughness.roughnessFactor : 1.0;

      if (metallicRoughness.metallicRoughnessTexture !== undefined) {
        pending.push(parser.assignTexture(materialParams, 'metalnessMap', metallicRoughness.metallicRoughnessTexture));
        pending.push(parser.assignTexture(materialParams, 'roughnessMap', metallicRoughness.metallicRoughnessTexture));
      }

      materialType = this._invokeOne(function (ext) {
        return ext.getMaterialType && ext.getMaterialType(materialIndex);
      });
      pending.push(Promise.all(this._invokeAll(function (ext) {
        return ext.extendMaterialParams && ext.extendMaterialParams(materialIndex, materialParams);
      })));
    }

    if (materialDef.doubleSided === true) {
      materialParams.side = THREE.DoubleSide;
    }

    const alphaMode = materialDef.alphaMode || ALPHA_MODES.OPAQUE;

    if (alphaMode === ALPHA_MODES.BLEND) {
      materialParams.transparent = true; // See: https://github.com/mrdoob/three.js/issues/17706

      materialParams.depthWrite = false;
    } else {
      materialParams.transparent = false;

      if (alphaMode === ALPHA_MODES.MASK) {
        materialParams.alphaTest = materialDef.alphaCutoff !== undefined ? materialDef.alphaCutoff : 0.5;
      }
    }

    if (materialDef.normalTexture !== undefined && materialType !== THREE.MeshBasicMaterial) {
      pending.push(parser.assignTexture(materialParams, 'normalMap', materialDef.normalTexture)); // https://github.com/mrdoob/three.js/issues/11438#issuecomment-507003995

      materialParams.normalScale = new THREE.Vector2(1, -1);

      if (materialDef.normalTexture.scale !== undefined) {
        materialParams.normalScale.set(materialDef.normalTexture.scale, -materialDef.normalTexture.scale);
      }
    }

    if (materialDef.occlusionTexture !== undefined && materialType !== THREE.MeshBasicMaterial) {
      pending.push(parser.assignTexture(materialParams, 'aoMap', materialDef.occlusionTexture));

      if (materialDef.occlusionTexture.strength !== undefined) {
        materialParams.aoMapIntensity = materialDef.occlusionTexture.strength;
      }
    }

    if (materialDef.emissiveFactor !== undefined && materialType !== THREE.MeshBasicMaterial) {
      materialParams.emissive = new THREE.Color().fromArray(materialDef.emissiveFactor);
    }

    if (materialDef.emissiveTexture !== undefined && materialType !== THREE.MeshBasicMaterial) {
      pending.push(parser.assignTexture(materialParams, 'emissiveMap', materialDef.emissiveTexture));
    }

    return Promise.all(pending).then(function () {
      let material;

      if (materialType === GLTFMeshStandardSGMaterial) {
        material = extensions[EXTENSIONS.KHR_MATERIALS_PBR_SPECULAR_GLOSSINESS].createMaterial(materialParams);
      } else {
        material = new materialType(materialParams);
      }

      if (materialDef.name) material.name = materialDef.name; // baseColorTexture, emissiveTexture, and specularGlossinessTexture use sRGB encoding.

      if (material.map) material.map.encoding = THREE.sRGBEncoding;
      if (material.emissiveMap) material.emissiveMap.encoding = THREE.sRGBEncoding;
      assignExtrasToUserData(material, materialDef);
      parser.associations.set(material, {
        type: 'materials',
        index: materialIndex
      });
      if (materialDef.extensions) addUnknownExtensionsToUserData(extensions, material, materialDef);
      return material;
    });
  }
  /** When THREE.Object3D instances are targeted by animation, they need unique names. */


  createUniqueName(originalName) {
    const sanitizedName = THREE.PropertyBinding.sanitizeNodeName(originalName || '');
    let name = sanitizedName;

    for (let i = 1; this.nodeNamesUsed[name]; ++i) {
      name = sanitizedName + '_' + i;
    }

    this.nodeNamesUsed[name] = true;
    return name;
  }
  /**
   * Specification: https://github.com/KhronosGroup/glTF/blob/master/specification/2.0/README.md#geometry
   *
   * Creates BufferGeometries from primitives.
   *
   * @param {Array<GLTF.Primitive>} primitives
   * @return {Promise<Array<BufferGeometry>>}
   */


  loadGeometries(primitives) {
    const parser = this;
    const extensions = this.extensions;
    const cache = this.primitiveCache;

    function createDracoPrimitive(primitive) {
      return extensions[EXTENSIONS.KHR_DRACO_MESH_COMPRESSION].decodePrimitive(primitive, parser).then(function (geometry) {
        return addPrimitiveAttributes(geometry, primitive, parser);
      });
    }

    const pending = [];

    for (let i = 0, il = primitives.length; i < il; i++) {
      const primitive = primitives[i];
      const cacheKey = createPrimitiveKey(primitive); // See if we've already created this geometry

      const cached = cache[cacheKey];

      if (cached) {
        // Use the cached geometry if it exists
        pending.push(cached.promise);
      } else {
        let geometryPromise;

        if (primitive.extensions && primitive.extensions[EXTENSIONS.KHR_DRACO_MESH_COMPRESSION]) {
          // Use DRACO geometry if available
          geometryPromise = createDracoPrimitive(primitive);
        } else {
          // Otherwise create a new geometry
          geometryPromise = addPrimitiveAttributes(new THREE.BufferGeometry(), primitive, parser);
        } // Cache this geometry


        cache[cacheKey] = {
          primitive: primitive,
          promise: geometryPromise
        };
        pending.push(geometryPromise);
      }
    }

    return Promise.all(pending);
  }
  /**
   * Specification: https://github.com/KhronosGroup/glTF/blob/master/specification/2.0/README.md#meshes
   * @param {number} meshIndex
   * @return {Promise<Group|Mesh|SkinnedMesh>}
   */


  loadMesh(meshIndex) {
    const parser = this;
    const json = this.json;
    const extensions = this.extensions;
    const meshDef = json.meshes[meshIndex];
    const primitives = meshDef.primitives;
    const pending = [];

    for (let i = 0, il = primitives.length; i < il; i++) {
      const material = primitives[i].material === undefined ? createDefaultMaterial(this.cache) : this.getDependency('material', primitives[i].material);
      pending.push(material);
    }

    pending.push(parser.loadGeometries(primitives));
    return Promise.all(pending).then(function (results) {
      const materials = results.slice(0, results.length - 1);
      const geometries = results[results.length - 1];
      const meshes = [];

      for (let i = 0, il = geometries.length; i < il; i++) {
        const geometry = geometries[i];
        const primitive = primitives[i]; // 1. create THREE.Mesh

        let mesh;
        const material = materials[i];

        if (primitive.mode === WEBGL_CONSTANTS.TRIANGLES || primitive.mode === WEBGL_CONSTANTS.TRIANGLE_STRIP || primitive.mode === WEBGL_CONSTANTS.TRIANGLE_FAN || primitive.mode === undefined) {
          // .isSkinnedMesh isn't in glTF spec. See ._markDefs()
          mesh = meshDef.isSkinnedMesh === true ? new THREE.SkinnedMesh(geometry, material) : new THREE.Mesh(geometry, material);

          if (mesh.isSkinnedMesh === true && !mesh.geometry.attributes.skinWeight.normalized) {
            // we normalize floating point skin weight array to fix malformed assets (see #15319)
            // it's important to skip this for non-float32 data since normalizeSkinWeights assumes non-normalized inputs
            mesh.normalizeSkinWeights();
          }

          if (primitive.mode === WEBGL_CONSTANTS.TRIANGLE_STRIP) {
            mesh.geometry = toTrianglesDrawMode(mesh.geometry, THREE.TriangleStripDrawMode);
          } else if (primitive.mode === WEBGL_CONSTANTS.TRIANGLE_FAN) {
            mesh.geometry = toTrianglesDrawMode(mesh.geometry, THREE.TriangleFanDrawMode);
          }
        } else if (primitive.mode === WEBGL_CONSTANTS.LINES) {
          mesh = new THREE.LineSegments(geometry, material);
        } else if (primitive.mode === WEBGL_CONSTANTS.LINE_STRIP) {
          mesh = new THREE.Line(geometry, material);
        } else if (primitive.mode === WEBGL_CONSTANTS.LINE_LOOP) {
          mesh = new THREE.LineLoop(geometry, material);
        } else if (primitive.mode === WEBGL_CONSTANTS.POINTS) {
          mesh = new THREE.Points(geometry, material);
        } else {
          throw new Error('THREE.GLTFLoader: Primitive mode unsupported: ' + primitive.mode);
        }

        if (Object.keys(mesh.geometry.morphAttributes).length > 0) {
          updateMorphTargets(mesh, meshDef);
        }

        mesh.name = parser.createUniqueName(meshDef.name || 'mesh_' + meshIndex);
        assignExtrasToUserData(mesh, meshDef);
        if (primitive.extensions) addUnknownExtensionsToUserData(extensions, mesh, primitive);
        parser.assignFinalMaterial(mesh);
        meshes.push(mesh);
      }

      if (meshes.length === 1) {
        return meshes[0];
      }

      const group = new THREE.Group();

      for (let i = 0, il = meshes.length; i < il; i++) {
        group.add(meshes[i]);
      }

      return group;
    });
  }
  /**
   * Specification: https://github.com/KhronosGroup/glTF/tree/master/specification/2.0#cameras
   * @param {number} cameraIndex
   * @return {Promise<THREE.Camera>}
   */


  loadCamera(cameraIndex) {
    let camera;
    const cameraDef = this.json.cameras[cameraIndex];
    const params = cameraDef[cameraDef.type];

    if (!params) {
      console.warn('THREE.GLTFLoader: Missing camera parameters.');
      return;
    }

    if (cameraDef.type === 'perspective') {
      camera = new THREE.PerspectiveCamera(THREE.MathUtils.radToDeg(params.yfov), params.aspectRatio || 1, params.znear || 1, params.zfar || 2e6);
    } else if (cameraDef.type === 'orthographic') {
      camera = new THREE.OrthographicCamera(-params.xmag, params.xmag, params.ymag, -params.ymag, params.znear, params.zfar);
    }

    if (cameraDef.name) camera.name = this.createUniqueName(cameraDef.name);
    assignExtrasToUserData(camera, cameraDef);
    return Promise.resolve(camera);
  }
  /**
   * Specification: https://github.com/KhronosGroup/glTF/tree/master/specification/2.0#skins
   * @param {number} skinIndex
   * @return {Promise<Object>}
   */


  loadSkin(skinIndex) {
    const skinDef = this.json.skins[skinIndex];
    const skinEntry = {
      joints: skinDef.joints
    };

    if (skinDef.inverseBindMatrices === undefined) {
      return Promise.resolve(skinEntry);
    }

    return this.getDependency('accessor', skinDef.inverseBindMatrices).then(function (accessor) {
      skinEntry.inverseBindMatrices = accessor;
      return skinEntry;
    });
  }
  /**
   * Specification: https://github.com/KhronosGroup/glTF/tree/master/specification/2.0#animations
   * @param {number} animationIndex
   * @return {Promise<AnimationClip>}
   */


  loadAnimation(animationIndex) {
    const json = this.json;
    const animationDef = json.animations[animationIndex];
    const pendingNodes = [];
    const pendingInputAccessors = [];
    const pendingOutputAccessors = [];
    const pendingSamplers = [];
    const pendingTargets = [];

    for (let i = 0, il = animationDef.channels.length; i < il; i++) {
      const channel = animationDef.channels[i];
      const sampler = animationDef.samplers[channel.sampler];
      const target = channel.target;
      const name = target.node !== undefined ? target.node : target.id; // NOTE: target.id is deprecated.

      const input = animationDef.parameters !== undefined ? animationDef.parameters[sampler.input] : sampler.input;
      const output = animationDef.parameters !== undefined ? animationDef.parameters[sampler.output] : sampler.output;
      pendingNodes.push(this.getDependency('node', name));
      pendingInputAccessors.push(this.getDependency('accessor', input));
      pendingOutputAccessors.push(this.getDependency('accessor', output));
      pendingSamplers.push(sampler);
      pendingTargets.push(target);
    }

    return Promise.all([Promise.all(pendingNodes), Promise.all(pendingInputAccessors), Promise.all(pendingOutputAccessors), Promise.all(pendingSamplers), Promise.all(pendingTargets)]).then(function (dependencies) {
      const nodes = dependencies[0];
      const inputAccessors = dependencies[1];
      const outputAccessors = dependencies[2];
      const samplers = dependencies[3];
      const targets = dependencies[4];
      const tracks = [];

      for (let i = 0, il = nodes.length; i < il; i++) {
        const node = nodes[i];
        const inputAccessor = inputAccessors[i];
        const outputAccessor = outputAccessors[i];
        const sampler = samplers[i];
        const target = targets[i];
        if (node === undefined) continue;
        node.updateMatrix();
        node.matrixAutoUpdate = true;
        let TypedKeyframeTrack;

        switch (PATH_PROPERTIES[target.path]) {
          case PATH_PROPERTIES.weights:
            TypedKeyframeTrack = THREE.NumberKeyframeTrack;
            break;

          case PATH_PROPERTIES.rotation:
            TypedKeyframeTrack = THREE.QuaternionKeyframeTrack;
            break;

          case PATH_PROPERTIES.position:
          case PATH_PROPERTIES.scale:
          default:
            TypedKeyframeTrack = THREE.VectorKeyframeTrack;
            break;
        }

        const targetName = node.name ? node.name : node.uuid;
        const interpolation = sampler.interpolation !== undefined ? INTERPOLATION[sampler.interpolation] : THREE.InterpolateLinear;
        const targetNames = [];

        if (PATH_PROPERTIES[target.path] === PATH_PROPERTIES.weights) {
          // Node may be a THREE.Group (glTF mesh with several primitives) or a THREE.Mesh.
          node.traverse(function (object) {
            if (object.isMesh === true && object.morphTargetInfluences) {
              targetNames.push(object.name ? object.name : object.uuid);
            }
          });
        } else {
          targetNames.push(targetName);
        }

        let outputArray = outputAccessor.array;

        if (outputAccessor.normalized) {
          const scale = getNormalizedComponentScale(outputArray.constructor);
          const scaled = new Float32Array(outputArray.length);

          for (let j = 0, jl = outputArray.length; j < jl; j++) {
            scaled[j] = outputArray[j] * scale;
          }

          outputArray = scaled;
        }

        for (let j = 0, jl = targetNames.length; j < jl; j++) {
          const track = new TypedKeyframeTrack(targetNames[j] + '.' + PATH_PROPERTIES[target.path], inputAccessor.array, outputArray, interpolation); // Override interpolation with custom factory method.

          if (sampler.interpolation === 'CUBICSPLINE') {
            track.createInterpolant = function InterpolantFactoryMethodGLTFCubicSpline(result) {
              // A CUBICSPLINE keyframe in glTF has three output values for each input value,
              // representing inTangent, splineVertex, and outTangent. As a result, track.getValueSize()
              // must be divided by three to get the interpolant's sampleSize argument.
              return new GLTFCubicSplineInterpolant(this.times, this.values, this.getValueSize() / 3, result);
            }; // Mark as CUBICSPLINE. `track.getInterpolation()` doesn't support custom interpolants.


            track.createInterpolant.isInterpolantFactoryMethodGLTFCubicSpline = true;
          }

          tracks.push(track);
        }
      }

      const name = animationDef.name ? animationDef.name : 'animation_' + animationIndex;
      return new THREE.AnimationClip(name, undefined, tracks);
    });
  }

  createNodeMesh(nodeIndex) {
    const json = this.json;
    const parser = this;
    const nodeDef = json.nodes[nodeIndex];
    if (nodeDef.mesh === undefined) return null;
    return parser.getDependency('mesh', nodeDef.mesh).then(function (mesh) {
      const node = parser._getNodeRef(parser.meshCache, nodeDef.mesh, mesh); // if weights are provided on the node, override weights on the mesh.


      if (nodeDef.weights !== undefined) {
        node.traverse(function (o) {
          if (!o.isMesh) return;

          for (let i = 0, il = nodeDef.weights.length; i < il; i++) {
            o.morphTargetInfluences[i] = nodeDef.weights[i];
          }
        });
      }

      return node;
    });
  }
  /**
   * Specification: https://github.com/KhronosGroup/glTF/tree/master/specification/2.0#nodes-and-hierarchy
   * @param {number} nodeIndex
   * @return {Promise<Object3D>}
   */


  loadNode(nodeIndex) {
    const json = this.json;
    const extensions = this.extensions;
    const parser = this;
    const nodeDef = json.nodes[nodeIndex]; // reserve node's name before its dependencies, so the root has the intended name.

    const nodeName = nodeDef.name ? parser.createUniqueName(nodeDef.name) : '';
    return function () {
      const pending = [];

      const meshPromise = parser._invokeOne(function (ext) {
        return ext.createNodeMesh && ext.createNodeMesh(nodeIndex);
      });

      if (meshPromise) {
        pending.push(meshPromise);
      }

      if (nodeDef.camera !== undefined) {
        pending.push(parser.getDependency('camera', nodeDef.camera).then(function (camera) {
          return parser._getNodeRef(parser.cameraCache, nodeDef.camera, camera);
        }));
      }

      parser._invokeAll(function (ext) {
        return ext.createNodeAttachment && ext.createNodeAttachment(nodeIndex);
      }).forEach(function (promise) {
        pending.push(promise);
      });

      return Promise.all(pending);
    }().then(function (objects) {
      let node; // .isBone isn't in glTF spec. See ._markDefs

      if (nodeDef.isBone === true) {
        node = new THREE.Bone();
      } else if (objects.length > 1) {
        node = new THREE.Group();
      } else if (objects.length === 1) {
        node = objects[0];
      } else {
        node = new THREE.Object3D();
      }

      if (node !== objects[0]) {
        for (let i = 0, il = objects.length; i < il; i++) {
          node.add(objects[i]);
        }
      }

      if (nodeDef.name) {
        node.userData.name = nodeDef.name;
        node.name = nodeName;
      }

      assignExtrasToUserData(node, nodeDef);
      if (nodeDef.extensions) addUnknownExtensionsToUserData(extensions, node, nodeDef);

      if (nodeDef.matrix !== undefined) {
        const matrix = new THREE.Matrix4();
        matrix.fromArray(nodeDef.matrix);
        node.applyMatrix4(matrix);
      } else {
        if (nodeDef.translation !== undefined) {
          node.position.fromArray(nodeDef.translation);
        }

        if (nodeDef.rotation !== undefined) {
          node.quaternion.fromArray(nodeDef.rotation);
        }

        if (nodeDef.scale !== undefined) {
          node.scale.fromArray(nodeDef.scale);
        }
      }

      parser.associations.set(node, {
        type: 'nodes',
        index: nodeIndex
      });
      return node;
    });
  }
  /**
   * Specification: https://github.com/KhronosGroup/glTF/tree/master/specification/2.0#scenes
   * @param {number} sceneIndex
   * @return {Promise<Group>}
   */


  loadScene(sceneIndex) {
    const json = this.json;
    const extensions = this.extensions;
    const sceneDef = this.json.scenes[sceneIndex];
    const parser = this; // THREE.Loader returns THREE.Group, not Scene.
    // See: https://github.com/mrdoob/three.js/issues/18342#issuecomment-578981172

    const scene = new THREE.Group();
    if (sceneDef.name) scene.name = parser.createUniqueName(sceneDef.name);
    assignExtrasToUserData(scene, sceneDef);
    if (sceneDef.extensions) addUnknownExtensionsToUserData(extensions, scene, sceneDef);
    const nodeIds = sceneDef.nodes || [];
    const pending = [];

    for (let i = 0, il = nodeIds.length; i < il; i++) {
      pending.push(buildNodeHierachy(nodeIds[i], scene, json, parser));
    }

    return Promise.all(pending).then(function () {
      return scene;
    });
  }

}

function buildNodeHierachy(nodeId, parentObject, json, parser) {
  const nodeDef = json.nodes[nodeId];
  return parser.getDependency('node', nodeId).then(function (node) {
    if (nodeDef.skin === undefined) return node; // build skeleton here as well

    let skinEntry;
    return parser.getDependency('skin', nodeDef.skin).then(function (skin) {
      skinEntry = skin;
      const pendingJoints = [];

      for (let i = 0, il = skinEntry.joints.length; i < il; i++) {
        pendingJoints.push(parser.getDependency('node', skinEntry.joints[i]));
      }

      return Promise.all(pendingJoints);
    }).then(function (jointNodes) {
      node.traverse(function (mesh) {
        if (!mesh.isMesh) return;
        const bones = [];
        const boneInverses = [];

        for (let j = 0, jl = jointNodes.length; j < jl; j++) {
          const jointNode = jointNodes[j];

          if (jointNode) {
            bones.push(jointNode);
            const mat = new THREE.Matrix4();

            if (skinEntry.inverseBindMatrices !== undefined) {
              mat.fromArray(skinEntry.inverseBindMatrices.array, j * 16);
            }

            boneInverses.push(mat);
          } else {
            console.warn('THREE.GLTFLoader: Joint "%s" could not be found.', skinEntry.joints[j]);
          }
        }

        mesh.bind(new THREE.Skeleton(bones, boneInverses), mesh.matrixWorld);
      });
      return node;
    });
  }).then(function (node) {
    // build node hierachy
    parentObject.add(node);
    const pending = [];

    if (nodeDef.children) {
      const children = nodeDef.children;

      for (let i = 0, il = children.length; i < il; i++) {
        const child = children[i];
        pending.push(buildNodeHierachy(child, node, json, parser));
      }
    }

    return Promise.all(pending);
  });
}
/**
 * @param {BufferGeometry} geometry
 * @param {GLTF.Primitive} primitiveDef
 * @param {GLTFParser} parser
 */


function computeBounds(geometry, primitiveDef, parser) {
  const attributes = primitiveDef.attributes;
  const box = new THREE.Box3();

  if (attributes.POSITION !== undefined) {
    const accessor = parser.json.accessors[attributes.POSITION];
    const min = accessor.min;
    const max = accessor.max; // glTF requires 'min' and 'max', but VRM (which extends glTF) currently ignores that requirement.

    if (min !== undefined && max !== undefined) {
      box.set(new THREE.Vector3(min[0], min[1], min[2]), new THREE.Vector3(max[0], max[1], max[2]));

      if (accessor.normalized) {
        const boxScale = getNormalizedComponentScale(WEBGL_COMPONENT_TYPES[accessor.componentType]);
        box.min.multiplyScalar(boxScale);
        box.max.multiplyScalar(boxScale);
      }
    } else {
      console.warn('THREE.GLTFLoader: Missing min/max properties for accessor POSITION.');
      return;
    }
  } else {
    return;
  }

  const targets = primitiveDef.targets;

  if (targets !== undefined) {
    const maxDisplacement = new THREE.Vector3();
    const vector = new THREE.Vector3();

    for (let i = 0, il = targets.length; i < il; i++) {
      const target = targets[i];

      if (target.POSITION !== undefined) {
        const accessor = parser.json.accessors[target.POSITION];
        const min = accessor.min;
        const max = accessor.max; // glTF requires 'min' and 'max', but VRM (which extends glTF) currently ignores that requirement.

        if (min !== undefined && max !== undefined) {
          // we need to get max of absolute components because target weight is [-1,1]
          vector.setX(Math.max(Math.abs(min[0]), Math.abs(max[0])));
          vector.setY(Math.max(Math.abs(min[1]), Math.abs(max[1])));
          vector.setZ(Math.max(Math.abs(min[2]), Math.abs(max[2])));

          if (accessor.normalized) {
            const boxScale = getNormalizedComponentScale(WEBGL_COMPONENT_TYPES[accessor.componentType]);
            vector.multiplyScalar(boxScale);
          } // Note: this assumes that the sum of all weights is at most 1. This isn't quite correct - it's more conservative
          // to assume that each target can have a max weight of 1. However, for some use cases - notably, when morph targets
          // are used to implement key-frame animations and as such only two are active at a time - this results in very large
          // boxes. So for now we make a box that's sometimes a touch too small but is hopefully mostly of reasonable size.


          maxDisplacement.max(vector);
        } else {
          console.warn('THREE.GLTFLoader: Missing min/max properties for accessor POSITION.');
        }
      }
    } // As per comment above this box isn't conservative, but has a reasonable size for a very large number of morph targets.


    box.expandByVector(maxDisplacement);
  }

  geometry.boundingBox = box;
  const sphere = new THREE.Sphere();
  box.getCenter(sphere.center);
  sphere.radius = box.min.distanceTo(box.max) / 2;
  geometry.boundingSphere = sphere;
}
/**
 * @param {BufferGeometry} geometry
 * @param {GLTF.Primitive} primitiveDef
 * @param {GLTFParser} parser
 * @return {Promise<BufferGeometry>}
 */


function addPrimitiveAttributes(geometry, primitiveDef, parser) {
  const attributes = primitiveDef.attributes;
  const pending = [];

  function assignAttributeAccessor(accessorIndex, attributeName) {
    return parser.getDependency('accessor', accessorIndex).then(function (accessor) {
      geometry.setAttribute(attributeName, accessor);
    });
  }

  for (const gltfAttributeName in attributes) {
    const threeAttributeName = ATTRIBUTES[gltfAttributeName] || gltfAttributeName.toLowerCase(); // Skip attributes already provided by e.g. Draco extension.

    if (threeAttributeName in geometry.attributes) continue;
    pending.push(assignAttributeAccessor(attributes[gltfAttributeName], threeAttributeName));
  }

  if (primitiveDef.indices !== undefined && !geometry.index) {
    const accessor = parser.getDependency('accessor', primitiveDef.indices).then(function (accessor) {
      geometry.setIndex(accessor);
    });
    pending.push(accessor);
  }

  assignExtrasToUserData(geometry, primitiveDef);
  computeBounds(geometry, primitiveDef, parser);
  return Promise.all(pending).then(function () {
    return primitiveDef.targets !== undefined ? addMorphTargets(geometry, primitiveDef.targets, parser) : geometry;
  });
}
/**
 * @param {BufferGeometry} geometry
 * @param {Number} drawMode
 * @return {BufferGeometry}
 */


function toTrianglesDrawMode(geometry, drawMode) {
  let index = geometry.getIndex(); // generate index if not present

  if (index === null) {
    const indices = [];
    const position = geometry.getAttribute('position');

    if (position !== undefined) {
      for (let i = 0; i < position.count; i++) {
        indices.push(i);
      }

      geometry.setIndex(indices);
      index = geometry.getIndex();
    } else {
      console.error('THREE.GLTFLoader.toTrianglesDrawMode(): Undefined position attribute. Processing not possible.');
      return geometry;
    }
  } //


  const numberOfTriangles = index.count - 2;
  const newIndices = [];

  if (drawMode === THREE.TriangleFanDrawMode) {
    // gl.TRIANGLE_FAN
    for (let i = 1; i <= numberOfTriangles; i++) {
      newIndices.push(index.getX(0));
      newIndices.push(index.getX(i));
      newIndices.push(index.getX(i + 1));
    }
  } else {
    // gl.TRIANGLE_STRIP
    for (let i = 0; i < numberOfTriangles; i++) {
      if (i % 2 === 0) {
        newIndices.push(index.getX(i));
        newIndices.push(index.getX(i + 1));
        newIndices.push(index.getX(i + 2));
      } else {
        newIndices.push(index.getX(i + 2));
        newIndices.push(index.getX(i + 1));
        newIndices.push(index.getX(i));
      }
    }
  }

  if (newIndices.length / 3 !== numberOfTriangles) {
    console.error('THREE.GLTFLoader.toTrianglesDrawMode(): Unable to generate correct amount of triangles.');
  } // build final geometry


  const newGeometry = geometry.clone();
  newGeometry.setIndex(newIndices);
  return newGeometry;
}

THREE.GLTFLoader = GLTFLoader;
} )();
